The use of communication cables which include a plurality of optical fibers is rapidly expanding. An optical fiber cable may comprise a plurality of glass fibers each of which is protected by at least one layer of a coating material. The optical fibers may be assembled into units in which the fibers are held together by binder ribbons to provide a core. In one manufacturer's line of cables, the core is enclosed by a plastic tube and a plastic jacket.
Many different design optical fiber cables are available commercially. There are cables which include metallic shields, non-metallic or metallic longitudinally extending strength members and those which include grease-like filling material or superabsorbent polymer waterblocking materials. A typical optical fiber cable which is used between central offices has an outer diameter which is on the order of about 0.5 inch.
Although the commercially available optical fiber cables fulfill specific needs, there is a demand for a simplistic optical fiber cable which may be used as a utility cable and which need not include some of the provisions included in the cables discussed hereinabove. For example, there is a need for a cable which may be used to restore service around a damage location in a communication line.
During the service life of an optical fiber cable, the cable may become damaged. This may occur, for example, through unintentional contact by various kinds of excavation equipment, by lightning or by repeated attack by animals such as gophers, for example. Such damage may be partial in which case one or several optical fibers may be interrupted, or the damage may be total, such as a complete cable cut, for example.
In any case, it becomes necessary to restore service as quickly as possible. This may be done through an expedited temporary arrangement while more work is under way to replace the damaged cable. Typically, the replacement is an equivalent or a cable having enhanced features.
A temporary arrangement must be one which is easily installed and which is low in cost. Elements of the arrangement which must include a cable must be capable of being packaged in a carrying case which is portable and, desirably, in one which may be carried by an individual from a vehicle to a field location at which a disruption to service has occurred.
The sought after cable of the temporary arrangement for restoring service which has been interrupted because of damage to an existing cable should be one which is simplistic in design yet is one which is capable of providing service at least on a temporary basis. It should be light in weight so as to render it portable and capable of being carried easily to damage locations. Also, inasmuch as it may be used on a temporary basis and may be discarded after such use, it should be one which is relatively low in cost. It should be flexible so that it may be installed easily without the need for mechanized installation equipment. And of course, because it includes optical fibers, it must be one which includes strength members so that the optical fibers are not overstressed.
Accordingly, what is sought after and what seemingly is not available in the art is a lightweight, small, low-cost optical fiber cable which has sufficient strength to allow it to be installed without damage to the optical fiber therein. The sought after cable should be very flexible and smaller in outer diameter and lighter in weight than typical optical fiber cables.